[MIPS] Eleminate interrupt migration helper use.

> #define hw_interrupt_type       irq_chip
> typedef struct irq_chip         hw_irq_controller;
> #define no_irq_type             no_irq_chip
> typedef struct irq_desc         irq_desc_t;

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/kernel/irq-mv6434x.c b/arch/mips/kernel/irq-mv6434x.c
index f9c763a..b117e64 100644
--- a/arch/mips/kernel/irq-mv6434x.c
+++ b/arch/mips/kernel/irq-mv6434x.c
@@ -136,7 +136,7 @@
 
 #define shutdown_mv64340_irq	disable_mv64340_irq
 
-struct hw_interrupt_type mv64340_irq_type = {
+struct irq_chip mv64340_irq_type = {
 	.typename = "MV-64340",
 	.startup = startup_mv64340_irq,
 	.shutdown = shutdown_mv64340_irq,